1. Field of the Invention
The present invention is directed to a photocell system for an automatic headlight activation system for automatically turning on and off headlights of a vehicle at an appropriate timing.
2. Discussion of the Background
Driving a vehicle in the late afternoon as the sun sets or as the weather and visibility worsens can be very dangerous if the operator of the vehicle does not turn on the headlights of the vehicle. In fact, in the United States it is a law to turn on vehicle headlights when it gets dark, and in many states of the United States it is also a law to turn on the vehicle headlights whenever it rains, as it is assumed that the visibility is decreased.
Obviously, all vehicles with headlights have headlight switches. However, such switches require a vehicle operator to remember to turn on the headlights before it is too late. Automatic headlight activators are known in the art. One class of such products will automatically activate vehicle headlights whenever the windshield wipers of a vehicle are energized. Another class of products will automatically activate and deactivate vehicle headlights whenever ambient light conditions fall below or exceed predetermined values. That is, in this second class of products, the headlights will be automatically activated when a certain level of darkness is reached and will be automatically deactivated when a certain level of lightness is reached.
Such conventional products, however, suffer from several drawbacks in their implementation. More particularly, each of these types of products requires a photocell usually mounted somewhere cleanly on a dash of the vehicle. When such photocells are factory installed, their operation is usually satisfactory. However, a significant problem arises for the after market where a customer buys a product and must mount the photocell on the dash of, as an example, a car but must mount the remaining portions of the circuit, i.e., the control for actually turning on and off the vehicle headlights, under the hood area. If the photocell is required to be located on the dash of the car, the vehicle operator must then drill a hole through the fire wall, and run the photocell portion through this hole up on to the dash of the car. In the after market environment, there are no very efficient and aesthetically acceptable ways to mount this photocell on the dash which will not provide a difficult installation, significantly detract from the appearance of the dash or cause damage to the dash. Conventional mounting methods of using double stick tape or screws usually detract from the appearance of the dash of the vehicle.
Such conventional automatic headlight activators usually have another feature in that the headlights can be programmed to remain on for a predetermined period of time after a vehicle is turned off. For example, in the evening when a vehicle operator is ready to get out of the vehicle, it is often convenient to have the headlights of the vehicle stay on for an additional period of time, for example 30 seconds, so that the area around the vehicle is lit when the vehicle operator is leaving the vehicle. Such a system is known in the art. However, such systems suffer from a drawback in that once set they are always operative, regardless of whether the vehicle operator wants such an operation at all times. That is, the problem with such conventional systems is that once the system is set the vehicle headlights will always come on and stay on for the predetermined period of time, for example the 30 seconds, whether the vehicle operator desires this feature or not. The vehicle operator thus does not have control over when this feature should be utilized.